Organotin compounds and process of preparation



used to produce the products.

portion of the organot'in or; all of the organotin being present in the compound as 'a six-fold' coordinate organestannate union. The new group of compounds may also involve the partial polymerization of more than one organostannate group to form dior tri organostannates. In laboratory preparation it is frequently possible to so control theactionjthat only one unique product is the principalresult of the reaction, but in commercial preparation certain materials may be. obtained which aie-mixtures of several of the possible products or the group. In the stabilization of chlorine-containing compositions such mixtures are entirely suitable. erties and characteristics of the organostannate products are dependent upon the type and ratio of the reactants selves may be solids, viscous semisolids or liquids. i The alcohol-reactant'may be aheterocyclic, substituted and unsubstituted, saturated and unsaturated aliphatic, 'or

The physical prop-' The products in theme I. t t t n1 a a Patented Apr. 8, 1958 substituted and unsubstituted aromatic hydroxyl comg,830,067 pound such as isooctyl alcohol, dihydroabietyl alcohol,

. octadecyl alcohol, lauryl alcohol, phenol, furfuryl alcohol, ORGANOTIN R E OF geraniol, etc; The dibasic acid may be a heterocyclic I 5 substituted, terpene substituted, saturated or unsaturated Hugh E. Ramsden, Metuchen, N. J., and Elliott L. Weiudicarboxy compound, such as maleic, itaconic, phthalic,

berg, Long Island City, N. Y., assiguors to Metal & succinic, adipic acids or anhydrides, etc. In this specifica: Therm Corporation, New i a corporation 'tion the term dibasic acid includes either the. acid; per. se of New Jersey or the anhydride of the dibasic acid. The bifunctional tin oxide may be selected from di-alkyl, diaryl or di-' N0 isegihitlttfiti 19554 aralkyl tin oxides such as dibutyl-, dimethyl-, ditolyl-', diphenyl-, dibenzyl-, tin oxides etc. Suitable mercapto- 29 cimms- (CL 269-429) alkanol derivative reactants include, for example, such 7 compounds as B-mercaptoethyl decanoate, B-mercapto- The present invention'relates to the preparation of ethyl di-isooctyl borate, 2- (or 3) mercaptopropyl-la six-fold coordinate organostannate derivative useful as laurate, l-mercapt propyl-Z-stearate, 2 (or3 or 4) mera heat and light stabilizer for chlorinated materials such capto-n butyl-1-(2-ethylhexoate), o(or m or p) mercaptoas vinyl chloride resins and the like and to stabilized benzyl benzoate, etc. The nature of the hydrocarbon compositions of matter containing said organostannate groups of the alcohol, dibasic acid, organotin oxide, and products. The products of this invention, furthermore, m'ercapt oalkan'olv derivative is not of controlling imporare six-fold coordinate organostannate derivatives contance. Any' substituents may be used provided they are taining both Sn-O and Sr1-S bonds. innocuous to the particular formulation and in the par- Many organotin compounds have heretofore been pro ticular manner in which the finished compound is to be posed as stabilizers for chlorine-containing resins. For used." 1 j J f 1 Y the most part, these have been organotin salts of organic Various procedures may be followed in preparing the carboxylic acids in which the tin has been in the cation 1 sulfur-containing organotin compounds of this invention. of the compound. Such compounds usually yield with However, We prefer to carry out the following reactions the chlorine-containing resins, transparent, nearly waterin the order given: white plastics with a considerable degree of resistance to 30 .Sublect to l If used m high a concentranqn C. React the'product of B with a mercaptoalkanol derivaand even sometimes at concentrations necessary to obtain five p 7 w I adequate stabilization to heat and/or light; Several of 1 these compounds have a tendencyto cause sticking of a Reaction is Carried Gut y mixing the ingredients and plastic formulation to the mill and calender rolls during heating until the mass becomes Clear. If mo e than on processing, I mole of acid per mole of alcohol is used the mass may This application is a continuation in part of U. S. av t layars but Q l The'temperature application S i l N0. 323,935 filed D b 3, 1952, in this step is not critical but is usually kept within the wherein is disclosed a new group of sulfur-containing range organotin heat and light stabilizers for chlorine-coritaina yi heaction'B the 'Ofganotih OXi S -j ing plastics and resins, which do. not cause grayingwhen ual y added 0 h 5 h Product Of A The reacformulated with resins containing traces of lead, and w l i sx e m p n e p u e f t mixture which do not spew even when used in excessive quantifies. US$1 h h lyfiwith ut th pp o O fixtemhl These sulfur-containing stabilizers are the reactionp rod A fi js ll t organqtin Oxide s n ad d it may be ucts of an alcohol or alcohols, a dibasic acid, -a bifunc" f fi i yfi s the temperature Y- PP Y Q tional tin oxide and a mercaptoacid ester, whereinsaid hi in prdcrlfi 'qmp c the reaction" The reaction products are present at least partially in the formfof a l ldg be mp tew the as agaihvhficomes u s six-fold coordinate compoundtan ia y le r- ,,P ly; the e pe a rai d? In accordance with this invention the group of sulfurh h? an F S y t0 efiect h c ar o containing organostannate stabilizers is the reaction prod- U E J-IY; s; 296 g e ab Q.;C--su1 fic s. not of an alcohol or alcohols, a dibasic acid, a bifuncjhef re r a ionp arried out the cle ar product, tional tin oxide and a mercaptoalkanol derivative. from B is cooled to about room p fl mriay tolhe The unique character of. this newgroup; ofisulfur-icon 1' h i 125 0"; -z hq n f ah y 25-30? Th the taining organotin products is dependent upo'nwat least a g m l p a hQ ad hY ad d 0 it. Reaction starts immediately a11d proceeds rapidly with evolution:

ofiheah. Thev reaction sisfjudged tojbe complete when heat evblut i onfceases.- ,Theprpduc't of reaction Cis the sulfur-containihg organotin compound of ourinvention. It is desirable to cool the product of "reaction'B before. proceeding withreaction'C, since' there is a tendency for, the temperature to rise during reaction C due to theheatj -of reaction. In small batches the natural cooling of the reaction vesselusually suffices to keep the temperature from rising too high, but in large batches it maybe ad- ,visabIe to remove the heat of'reaction by cooling coils or L water jackets. i

The relative quantities o f reac tants' utilizable in the obtention of the preseiitreaction products maybe varied over a wide range. It ises'sential, however, that certain broad limits be maintained to retain the advantages of u the products of the present invention. The simplest form of'product obtained has a generalized structure of the following type. t

wherein R=alkyl, aryl or aralkyl, Y=coordination' groups, coordinated through or S and b is a varying charge dependent upon the nature of the Y s.

It should be noted that the tin atom in the above structure is in an electronic condition analogous to that of the stannate ion.

the type of structure which is producedin the present invention, the simplest product possible by the co-reacw tion of isooctyl alcohol, maleic anhydride, dibutyl tin' oxide and B-mercaptoethyl decanoate would be either OoCCH=C -COOCHH K soirnoo 00 B" H: Sn

SCaH4OOCCIHl6 0o o-on=ono 00081111 or t o0 G-CH=OH-C 0 coin" soirno ocean I (C4Ha):Sn n

depending upon the amount of dibutyl tin'oxide usedin the reaction. That these products are not simplejsalts may be proved by varying the amount of-mercaptoethyl decanoate used in the preparation. Aslonga as the amountof mercaptoethyl decanoate used, isstoichiometrically less than the amountrequired by the above required'formulations, it will be found impossible to remove any of the mercaptoethyl decanoate by vacuum distillation. When the amount of mercaptoethyl decanoate added is about 10%fin excess of that required by .the'

above formulations, the excess over the stoichiometrically 1 required amount may be recovered by vacuum distillation from the product. p a

In general terms the anionsof' have generalized structures as follows:

the simplest members of the group of compounds, claimed in this invention may R g s S R t Z \I l/ l/ TOCCDOOOSn-OOCDOOO-SnOOODCO0Sn-OOCDCOOT I I R s s R 5 Q. Q Q

R l j QS- SI1-SQ 0 0 O v 0 0 o D T D o 0 0 (2 i O R o 0: D000 0 R ln I/ R i oooDo=o" s R Q Q 0 'r t It canbe readily recognized that the possible'formulations of the tri stannate ions may be further extended by cross' linki-ng of the adducts in many varied combinations. While we believe these above structures to fairly represent the anionic nature of the invention, we are not limited to the specific structure cited.

protons or of sufiicient organotin cations to form neutral complexes.

The proportions of reactants need not be chosen so as to be stoichiometric vfor any particular one of the types since mixtures containing any of them are effective sta bilizers. However, in order to realize the advantages of the products of this invention over prior art stabilizers, it is necessary that the relative proportions of the reactants meet. the following criteria, wherein A defines the moles of alcohol, B defines the moles of dibasic acid, C defines the moles of organotin oxide and D defines the moles of mercaptoalkanol derivatives:

'gshould be Within the range of to l,

should bewithin the range of 0.2 to 2, and Csliould have a value between to A One preferred product has equimolecular quantities of alcohol, dibasic acid, organotin oxide and mercaptoalkanol derivative,

following molecular ratios: t

A 2B-A 5 g=about 0.9J

Still: another preferred product may have the following molecular ratios:

A 2BA 5% 2 ,;-=about 0.7

' The following examples arefurther illustrative of these 1 mole isooctyl alcohol and 1 mole maleic anhydride were heated in aglass container to a temperature of C.- C.,' until the interaction was completed. 1 mole 75 dibutyltin oxide was added gradually to theliquid mix The organo stannate ions represented above may be electrically satisfied by the presence in the product of Another preferred product has the at a temperature of 90-100 C. The oxide dissolved readily in said liquid with the initial evolution of heat. After all the oxide was added, the temperature was raised to 130 C. At this temperature, the mixture was filtered yielding a clear yellow liquid. This liquid was cooled to 25-30 C. To 22.3 gms. of the above reaction product was added 11.6 gms. of B-mercaptoethyl decanoate, yielding the desired stabilizer.

Example 11 1 mole isooctyl alcohol, 1 mole maleic anhydride and 1 mole dibutyl tin oxide were treated as in Example I. To 19.2 gms. of this product was added 15.8 gms. B-mercaptoethyl di-isooctyl borate, yielding the desired stabilizer..

These organotin reaction products will function as stabilizers for compositions containing chlorinated materials, particularly vinyl chloride containing resin compositions such asvinyl chloride polymer and copolymer resins containing plasticizers, and when intimately dispersed therein, will provide plastic compositions of improved resistance to heat and light deterioration. Films are obtained from the aforesaid plastic compositions which exhibit a high degree of stability. The optimum concentration of the aforesaid organotin derivatives, useful as a stabilizer is about 1% based on the weightof the chlorinated material, although .3-l% may also be utilized. The chlorinated composition containing this concentration of stabilizer produces a stable plastic film, which does not darken at elevated temperatures as evidenced by the following results.

In order to test the behavior of the stabilizers ofthis invention in polyvinyl chloride plastics, the product of each of the examples given above was used to make up a plastic composition containing:

100 parts of a commercial polyvinyl chloride resin, known to contain about 7 parts per million of lead 50 parts of di-Z-ethylhexyl phthalate (plasticizer) 1% by weight of the resins of stabilizer.

The ingredients were mixed, then milled at 320 F. on a differential speed, 2-roll mill for 5 minutes after which theplastic composition was taken 011 the mill as a sheet about 40 mils thick. 1" x 6 strips were cut from this sheet and subjected to aging in a circulating air oven at 350 F. Excellent heat stability of the sheets was found in each instance. Even after oven aging at 350 C. for an hour the test samples of Examples I and II were virtually colorless with very little color change. Other samples of the 40 mil sheets were exposed to aging in sunlight for about 1 month. No sweating or spewing was observed in any case. Excellent clarity and finish were obtained wifla the stabilizers of Examples I and II.

Other tests were made using other commercial polyvinyl chloride homoand co-polymer resins in place of the lead-containing resin described above. In each instance the resulting plastic sheets were found to be highly stable to heat. I I

The product of the examples were also tested in compositions containing higher and lower concentrations of stabilizer. These all show a high order of heat stability.

The plastics prepared with 1% by weight of the sta bilizers of this invention were also tested with regard to the staining of lead compound-stabilized plastics by the following procedure. A sample of the milled plastic sheet was clipped to a sheet of similar size made up from the following formulation:

100 parts polyvinyl chloride resin (Geon 101) 50 parts di-2-ethylhexyl phthalate 10 parts titanium dioxide pigment (Titanox A-LO) 2 parts basic lead carbonate 2 parts Dyphos (basic lead phosphite) /2 part DS-207 (dibasic lead stearate) The two sheets held in contact by the clips were placed in a 4 ounce bottle which was then sealed and placed in a'circulating air oven at 200 F. for 72 hours. Any staining of the white, lead stabilized sheet was then noted. The products of Examples I and H, did not show any stain. The light stabilizing effectiveness of several of the products ofthis invention were studied by means of Fade-O-Meter tests carried out on polyvinyl chloride plastic sheets containing them. They were found to be good light stabilizers, superior to many commercial light stabilizers.

Among the other uses of the organotin derivatives are their use as stabilizers for other chlorinated mate rials, as rubber accelerators, rubber antioxidants, lube oil additives, and polymerization accelerators.

While the invention has been described with reference to various examples and embodiments, it will be apparent to those skilled in the art that various modifications may be made, and equivalents substituted therefor, without departing from the principles and true nature of the present invention.

What is claimed is:

1. A method of preparing a sulfur-containing organotin compound which comprises: (1) esterifying B moles of a dibasic acid compound selected from the group consisting of dibasic acids of formula HOOCR'COOH and their anhydrides, with A moles of a hydroxy compound of formula ROH; (2) reacting the reaction product of (1) with C moles of an organotin oxide of formula R" SnO; (3) and reacting the reaction product of (2) with D moles of an ester selected from the group con sisting of mercaptoalkanol esters of hydrocarbon monocarboxylic acids and mercaptoalkanol borates; wherein R and R" are monovalent hydrocarbon radicals, R is a divalent hydrocarbon radical,

is withinthe range of to 1;

is within the range of .2 to 2; and C has a value of between 2. A process according to claim 1 wherein the ratio of A:B:C:D=1:l:1:1.

3. A process according to claim 1 wherein 5. A method of preparing a sulfur-containing organotin stabilizer which comprises: esten'fying B moles of a dibasic acid compound selected from the group consisting of dibasic acids of formula HOOCR'COOH and their anhydrides, with A moles of a hydroxy compound of formula ROH at a temperature of about 75-100 C. to form a liquid product; gradually adding to said liquid product and dissolving therein C moles of an organotin oxide of formula R" SnO; elevating the temperature of the mixture so formed to about C. until the liquid clarifies, cooling said mixture to about room temperature and adding thereto D moles of an ester selected from the group, consisting of,mercaptoalk anol esters of hydrocarbon monocarboxylic acids and mercaptoalkanol borates; wherein RandRTare monovalent hydrocarbon radicals, R" is a divalent hydrocarbon radical,

is within the range of V2 to is within the range of .2 to 2; and C has a value of between 2B-A+D 2B. -A

6. A process according to claim 5 wherein the ratio of A:B:C: D==1:1:1:1.

7. A process according to claim 5 wherein 9. A method of preparing .a sulfur-containing organetin compound which comprises reacting 1 mole of isooctyl alcohol and 1 mole of maleic anhydride ata temperature of about 75 C. to 100 C. until the reaction is completed and a liquid mix is formed, gradually adding 1 mole of dibutyltin oxide to said liquid mix at a temperature of about 90l00- 0., raising the temperature to 130 C. after all of said oxide is added, filtering the mixture at this temperature, whereby a clear yellow liquid is obtained, cooling theyellow liquid to about 25 30 C., reacting about 11.6 gms. of p-mercaptoethyl decanoate' with about 22.3 gms. of said yellow liquid and recovering the reaction product.

10. A method of preparing a sulfur-containing organotin compound which comprises reacting 1 mole of isooctyl alcohol and 1 mole of maleic anhydride ata temperature of about 75 to 100 C. until the reaction is completed and a liquid mix is formed, gradually adding 1 mole of dibutyltin oxide to said liquid mix at a temperature of about 90 100 0, raising the temperature to 130 C. after all of said oxide is added, filtering the mixture at this temperature, whereby a clear yellow liquid is obtained, cooling the yellow liquid to about C., reacting about 19.2 gms. of this product with about 15.8 gms. of fl-mercaptoethyl diisooctyl borate, and recovering the reaction product. i i

11.. As a composition of matter the reaction product of the process of claim 1.

12. As a composition of matter the of the process of claim 2.

13. As a composition of matter the of the process of claim 3.

14. As a composition of matter the reaction product reaction product reaction product i of the process of claim 4.

reaction product reaction product reaction product reaction product reaction product of the process of claim 9.

20. As a composition of matter the reaction product of the process'of claim 10.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A METHOD OF PREPARING A SULFUR-CONTAINING ORGANOTIN COMPOUND WHICH COMPRISES: (1) ESTERIFYING B MOLES OF A DIBASIC ACID COMPOUND SELECTED FROM THE GROUP CONSISTING OF DIBASIC ACIDS OF FORMULA HOOCR''COOH AND THEIR ANHYDRIDES, WITH A MOLES OF A HYDROXY COMPOUND OF FORMULA ROH, (2) REACTING THE REACTION PRODUCT OF (1) WITH C MOLES OF AN ORGANOTIN OXIDE OF FORMULA R"2SNO, (3) AND REACTING THE REACTION PRODUCT OF (2) WITH D MOLES OF AN ESTER SELECTED FROM THE GROUP CONSISTING OF MERCAPTOALKAANOL ESTERS OF HYDROCARBON MONOCARBOXYLIC ACIDS AND MERCATOALKANOL BORATES, WHEREIN R AND R" ARE MONOVALENT HYDROCARBON RADICALS, R'' IS A DIVALEN HYDROCARBON RADICAL, 